光通信技术2026，Vol.50Issue(3)：58-64,7.DOI:10.13921/j.cnki.issn1002-5561.2026.05.010
低损耗超紧凑薄膜铌酸锂端面耦合器设计
Design of a low-loss ultra-compact thin-film lithium niobate edge coupler
摘要
Abstract
To address the high coupling loss caused by mode field mismatch between thin-film lithium niobate(TFLN)wave-guides and single-mode fibers,a low-loss,ultra-compact TFLN edge coupler is designed.A three-layer nano-slot structure is ad-opted,and a SiON cladding is added outside the TFLN to enlarge the mode field diameter and improve the edge coupling effi-ciency.By optimizing the segment lengths of the waveguide and the etching tilt angle,adiabatic mode conversion and compact integration are achieved.Finite element analysis simulations are performed,and the results show that in the wavelength range of 1 524～1 572 nm,the maximum coupling losses at the input and output ports are 0.4 dB and 0.36 dB,respectively.The total device length is only 115 μm,and the alignment tolerance reaches±0.7 μm.The coupler exhibits excellent com-pactness and alignment tolerance while maintaining low loss,offering an efficient and reliable edge-coupling solution for photonic integrated systems.关键词
薄膜铌酸锂/端面耦合器/高效耦合/对准容差Key words
thin-film lithium niobate/edge couplers/efficient coupling/alignment tolerance分类
信息技术与安全科学引用本文复制引用
熊斌,蒋品群,宋树祥,尹怡辉,杨万里,李跃..低损耗超紧凑薄膜铌酸锂端面耦合器设计[J].光通信技术,2026,50(3):58-64,7.基金项目
广西科技重大专项基金项目(桂科AA22068056)资助. （桂科AA22068056）
